List.drop_succ_sym: law of bend-mathlib@0.8.1.0
Import: import bend-mathlib@0.8.1.0/list.bend as List
Lines 3165-3172 of bend-mathlib@0.8.1.0/list.bend: https://jend.leeeet.dev/read.txt?path=bend-mathlib@0.8.1.0/list.bend&start_line=3165&end_line=3172

import Base

# Dropping n + 1 elements of a cons drops its head and n from its tail, reversed to rewrite toward the simple side.
law drop_succ_sym:
  for -a: Quant
  for -A: Kind(a)
  for -x: A
  for -xs: List<a, A>
  for -n: Nat
  {List.drop(a, A, xs, n) == List.drop(a, A, x <> xs, 1n+n) : List<a, A>}

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.drop
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=bend-mathlib@0.8.1.0/list.bend&name=drop_succ